package com.start.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.start.reggie.utils.BaseContext;
import com.start.reggie.utils.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否登录完成
 */
@Slf4j
@WebFilter(filterName = "webFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {

    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获取本次请求的URI
        String uri = request.getRequestURI();
        log.info("本次拦截到请求：{}",uri);

        //定义不需要处理的请求路径
        String[] uris = {
                "/backend/**",
                "/front/**",
                "/employee/login",
                "/employee/logout",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };

        //2.判断本次请求是否需要处理
        boolean check = check(uri,uris);

        //3.如果不需要处理，则直接放行
        if (check){
            log.info("本次请求{}不需要处理",uri);
            filterChain.doFilter(request,response);
            return;
        }

        //4-1.判断登录状态，如果已登录，则直接放行
        Long empId = (Long) request.getSession().getAttribute("employee");
        if (empId != null){
            log.info("用户{}已登录",empId);

            //将当前登录用户id放入ThreadLocal封装工具类
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request,response);

            return;
        }

        //4-2.判断登录状态，如果已登录，则直接放行
        Long userId = (Long) request.getSession().getAttribute("user");
        if (userId != null){
            log.info("用户{}已登录",userId);

            //将当前登录用户id放入ThreadLocal封装工具类
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);

            return;
        }

        //5.如果未登录，则返回未登录结果，通过输出流方式向客户端页面响应数据
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));

    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param requestURI
     * @param uris
     * @return
     */
    public boolean check(String requestURI,String[] uris){
        for (String uri : uris) {
            boolean match = PATH_MATCHER.match(uri, requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }

}
